Bus bar clamp



y 2, 1933- H. B. MASSEY ET AL 1,906,915

BUS BAR CLAMP Filed Oct. 4, 1930 2 Sheets-Sheet 1 May 2, 1933. H, B, M EET AL 1,906,915

' BUS BAR CLAMP Filed Oct. 4, 1930 2 Sheets-Sheet -22 Patented May 2,1933 bolt pressures.

UNITED STATES PATENT OFFICE HEMSTiEY B. MASSEY AND OLAV MASENG, 0FGBEENSBURG, PENNSYLVANIA, ASSIGN- ORS TO RAILWAY AND INDUSTRIALENGINEERING COMPANY, OF GREENSBUEG, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA BUS BAR CLAMP Application filed october 4, 1930. Serial No.486,455.

This invention relates to bar conductor clamps of the type employed insplicing rectangular bus bar sections or in tapping to the same.

'As a matter of convenience, it has been the recent practice to makesplices or tapped connections by clamping the rectangular bus barsections together with metal clamps having two, three or four bolts. Inmany respects such clamped connections have been inferior to the oldertype of connections in which the bars were drilled and the clamp boltsextended through the bus bar sections. The-metal plate clamps are opento the serious objection that the plates deflect under the clampingpressure and concentrate the pressure in local areas adjacent theclamping bolts. llt has been found impractical to make the plates ofsuch heavy construction that such deflection is eliminated, and attemptsto compensate for such deflection by an initial crowning of the plateshave failed due to the difficulty in obtaining the intended curvatureand/or the intended bolt pressure, as well as to local imperfections inthe metal plates.

An object of the present invention is to provide bus bar clamps ofrelatively light construction which, within the ultimate strength of thematerial, will present substantially plane surfaces to the bus bars forall More particularly, an object is to provide a bus bar clamp of suchconfiguration that v the contact surface remains planar under acombination of bending and torque stresses established by the clampingbolts. 1

These and other objects of the invention will be apparent from thefollowing specification when taken with the accompanying drawings, inwhich Fig. 1 is a diagrammatic view illustrative of the invention,

Fig. 2 is a side elevation 'of a bus bar splice made with a clampembodying the invention,

Fig. 3 is a vertical section through the same,

Fig. 4 is a central section through another form of clamp, and

Figs. 5 and 6 are a front and side elevation,

respectively, of another form of clamp embodying the invention.

Referring to Fig. 1, it can be shown experimentally that ifapproximately uniform pressures, indicated by arrows P, are applied toradial extensions 1 on a wire annulus 2, the annulus will be deformedbut there will be substantially no tendency for any part of the annulusto rise above the plane support 3 upon which the annulus rests. In otherWords, the lower surface of the annulus re mains planar under theinfluence of the bendmg and torque stresses due to the appliedpressures.

As shown in Fig. 2, a clamp of general form of this wire annulus isemployed to join the ends of bus bars 1, 5. Each clamp comprises a ring6 of circular cross-section having four arms 7 projecting radiallytherefrom to receive clamping bolts 8.

As shown inFig. 4, the clamp takes the form of a short cylinder 9 havingan annular clamping surface 10 at one end, and radial clamping arms 11extending from the other end. If desired, the outer end of the cylindermay be closed, in whole or in part, by a diaphragm or end wall 12. Toreinforce the clamping arms 11, and to distribute the stresses to thecylinder 9, the clamping arms Clamping surface 14 is provided by the endof a short cylinder 15 from which extend three radial arms 16, theangular disposition of the arms being such that two lie at one edge ofthe bus bar, and the third is symmetrically located at the oppositeedge. The outer surfaces of the clamping arms have peripheral ribs 17,the ribs of adjacent arms preferably merging at sections which form, ineffect, extensions of the cylinder 15. The inner faces of the radialarms have similar reinforcing and stress distributing flanges 18 whichextend to the cylinder 15 and preferably underlie the outer reinforcingribs 17 The outer end of the cylindrical portion 15 is closed by an endwall 19, which may have central aperture 20 for receiving a clamp boltin caseit is desired to pass such a bolt directly through erably lie inthe same plane as the closure, By appropriate design, the outerreinforcing ribs 17 may be omitted, but the lower flanges should," ingeneral, be retained to effect a better distribution of theystressestending to deform the cylindrical portion It will be apparent that theclamping pressure must be applied at more than two points if sphericaldeformation, as distinguished from cylindrical deformation, of theannular clamping surface is to he obtained. With this limitation, thenumber of clamping arms secured to the cylindrical section of the clampmay be varied at will in accordance with the particular form of the barsto be clamped.

We claim:

1. A bus bar clamp comprising a body having an annular contact surfacefor'engagement with the plane surface of a bus bar, and means forapplying clamping pressure normal to and offset from the contactsurface.

2. A bus bar clamp comprising a body having an annular contact surfacefor engagement with the plane surface of a bus bar, and means forapplying clamping pressure normal to said surface and in a plurality ofintersecting planes.

3. A bus bar clamp, as set forth in claim 2, wherein said meanscomprises clamping arms extending substantially radially from said body.

4. A bus bar clamp comprising an annular body having an annular contactsurface for engagement with the plane surface of a bus bar, and meansfor applying clamping pressures normal to and offset from the contactsurface:

5. The invention as set forth in claim 4, wherein said means comprisesclamping arms extending substantially radially from said body to definea plurality of planes normal to said contact surface. a

6. A bus bar clamp member comprising an annular body portlon terminatingat one face in an annular contact surface, and clamping arms projectingsubstantially radially from said body portion to define a plurality ofplanes normal to said contact surface.

7. A bus bar clamp comprising a cylindrical portion terminating at oneend in an annular contact surface, and more than two clamping armsprojecting radially from the opposite end of said cylindrical portion.

8. In a bus bar clamp, a body having a cylindrical portion, a diaphragmclosing one end of said portion, an annular clamping area at theopposite end of said portion, and means for applying clamping pressurealong lines parallel to the axis of said cylindrical portion and offsetfrom axial alincment with said portion.

9. In a bus bar clamp for bus bars of rectangular cross-section, a clampmember comprising a hollow cylindrical portion terminating at one end ina plane substantially normal to the axis of said cylindricalportion,thereby to provide an annular contact surface for contact with a busbar,and lugs extending radially-from the opposite end of said cylindricalportion, said lugs being apertured to receive clamp bolts,

10. A bus bar clamp for bus bars of rectangular cross-section,comprising a pair of clamping members, each member comprising an annularsection having a contact surface of annular contour lying in a planesubstantially normal to the axis of said annular section, and clampingarms projecting radially from said annular section, said clamping armsbeing apertured to receive bolts for drawing said members towards eachother, thereby to draw the opposed annular contact surfaces of saidmembers against the opposite faces of the bus bars.

11. The invention as set forth in claim 10, wherein said annularsections comprise rings of circular cross-section.

12. The invention as set forth in claim 10, wherein said annularsections comprise cylinders, and said radial clamping arms are spacedaxially from the annular contact ends of the respective cylinders.

13. The invention asset forth in claim 10, wherein said annular sectionscomprise cylinders, and said radial clamping arms are spaced axiallyfrom the annular contact ends of the respective cylinders, incombination with reinforcing ribs on said arms and merging into saidcylinders.

In testimony whereof, we affix our sig-

